* include/ruby/ruby.h (struct RStruct): no longer.
* internal.h (struct RStruct): moved here.
* struct.c (rb_struct_ptr): a compensation function for the lack
of RSTRUCT_PTR. But now that we have RSTRUCT_GET/SET, that must
not be used anyway. I mark this deprecated. Dont use it.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@55788 b2dd03c8-39d4-4d8f-98ff-823fe69b080e